According to a US observational study digital overload could be linked to a modest but significant rise in new ADHD behaviours, offering a warning to parents about the potential dangers of too much screen time.
A Daily Maverick report says the findings were based on nearly 2,600 Los Angeles teens who answered survey questions over a two-year period – making it one of the largest and longest studies on the topic to date. The more social media, streaming video, text messaging, music downloads or online chats they engaged with, the more likely they were to report symptoms like difficulty organising and completing tasks, or trouble remaining still.
About 10% of youths who said they commonly used digital media platforms frequently showed new ADHD symptoms over the study period, said the study. In contrast, 4.6% of students who were not frequent users of any digital activity showed ADHD symptoms.
Researchers cautioned that the rise in ADHD symptoms was “modest” and at least some of the effect might be explained by confounding factors. Also, since the study was observational in nature and was based on survey responses by the teens themselves, researchers said they could not prove that smartphone use actually caused ADHD symptoms.
Still, the report says the findings offer a solid basis for more research because “this was a statistically significant association,” said Adam Leventhal, a professor of preventive medicine and psychology at the University of Southern California. “We can say with confidence that teens who were exposed to higher levels of digital media were significantly more likely to develop ADHD symptoms in the future.”
Previous studies have shown that ADHD, a psychiatric condition involving persistent difficulty sustaining attention, hyperactivity and impulsivity, affects about seven percent of youths in the US and may be on the rise in some populations. Earlier studies examining the effect of television watching and playing video games found modest increases in ADHD among children.
According to Jessica Agnew-Blais, a post-doctoral research fellow at the Institute of Psychiatry, Psychology and Neuroscience at King’s College London, the authors were “rightfully cautious not to over-interpret” their findings. “The authors only assess ADHD symptom frequency, so it remains unclear whether relatively small changes in ADHD symptom frequency over these two years are disruptive or impairing in everyday life,” she said. “It is worth noting that over 80% of students reported high frequency use of digital media, and the vast majority of these students do not have elevated ADHD symptoms.”
The report says another expert who was not involved in the study, Andy Przybylski, an associate professor at the Oxford Internet Institute, University of Oxford, described the research as “interesting” but “tentative.” “The study is a proof of concept that tells us we need very large samples when we design future studies because the possible effects are extremely small,” he said.
The next studies on the topic should move away from self-reported survey answers and include clinical diagnoses and external measurements of device use, experts suggested.
Importance: Modern digital platforms are easily accessible and intensely stimulating; it is unknown whether frequent use of digital media may be associated with symptoms of attention-deficit/hyperactivity disorder (ADHD).
Objective: To determine whether the frequency of using digital media among 15- and 16-year-olds without significant ADHD symptoms is associated with subsequent occurrence of ADHD symptoms during a 24-month follow-up.
Design, Setting, and Participants: Longitudinal cohort of students in 10 Los Angeles County, California, high schools recruited through convenience sampling. Baseline and 6-, 12-, 18-, and 24-month follow-up surveys were administered from September 2014 (10th grade) to December 2016 (12th grade). Of 4100 eligible students, 3051 10th-graders (74%) were surveyed at the baseline assessment.
Exposures: Self-reported use of 14 different modern digital media activities at a high-frequency rate over the preceding week was defined as many times a day (yes/no) and was summed in a cumulative index (range, 0-14).
Main Outcomes and Measures: Self-rated frequency of 18 ADHD symptoms (never/rare, sometimes, often, very often) in the 6 months preceding the survey. The total numbers of 9 inattentive symptoms (range, 0-9) and 9 hyperactive-impulsive symptoms (range, 0-9) that students rated as experiencing often or very often were calculated. Students who had reported experiencing often or very often 6 or more symptoms in either category were classified as being ADHD symptom-positive.
Results: Among the 2587 adolescents (63% eligible students; 54.4% girls; mean [SD] age 15.5 years [0.5 years]) who did not have significant symptoms of ADHD at baseline, the median follow-up was 22.6 months (interquartile range [IQR], 21.8-23.0, months). The mean (SD) number of baseline digital media activities used at a high-frequency rate was 3.62 (3.30); 1398 students (54.1%) indicated high frequency of checking social media (95% CI, 52.1%-56.0%), which was the most common media activity. High-frequency engagement in each additional digital media activity at baseline was associated with a significantly higher odds of having symptoms of ADHD across follow-ups (OR, 1.11; 95% CI, 1.06-1.16). This association persisted after covariate adjustment (OR, 1.10; 95% CI, 1.05-1.15). The 495 students who reported no high-frequency media use at baseline had a 4.6% mean rate of having ADHD symptoms across follow-ups vs 9.5% among the 114 who reported 7 high-frequency activities (difference; 4.9%; 95% CI, 2.5%-7.3%) and vs 10.5% among the 51 students who reported 14 high-frequency activities (difference, 5.9%; 95% CI, 2.6%-9.2%).
Conclusions and Relevance: Among adolescents followed up over 2 years, there was a statistically significant but modest association between higher frequency of digital media use and subsequent symptoms of ADHD. Further research is needed to determine whether this association is causal.
Chaelin K Ra; Junhan Cho; Matthew D Stone; Julianne De La Cerda; Nicholas I Goldenson; Elizabeth Moroney; Irene Tung; Steve S Lee; Adam M Leventhal